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speech recognition and discrimination testing is done to determine the patient’s minimum inten-
sity levels required to detect speech and discriminate words. Speech audiometry also addresses the
patient’s loudness comfort level.
Newborns, Infants, and Hard- to- Test Populations
It is vitally impor tant to detect hearing loss and deafness in children as early as pos si ble.
According to the American Acad emy of Audiology (2015), approximately 6 in 1,000 babies— more
than 4,000 children each year— are born with a hearing loss. A child with unidentified significant
hearing loss or deafness suffers psychologically, educationally, and socially. One way of testing
newborns, infants, and hard- to- test populations (e.g., intellectually disabled, with reduced con-
sciousness, or demented) is behavioral: examining actions such as the head turning, startle ref lex,
or sucking be hav ior of the infant or child in response to auditory stimuli. Technological advances
have dramatically improved newborn and infant hearing screening procedures. “The conventional
methods for audiological evaluations of infants and young children are otoacoustic emissions
(OAE), behavioral testing and tympanometry. These procedures also can be used for pediatric
populations with special needs, but modifications may be required” (Klimas, 2003, p. 23). Klimas
notes that auditory brainstem responses (ABRs) may be mea sured while the patient is sedated and
can be useful for difficult populations who cannot be tested behaviorally.
OAEs are sounds emanating from the external ear as a result of cochlear vibration. According
to Martin and Clark (2003), there are two classes of OAE: spontaneous and transient- evoked
(TEOAE). Spontaneous OAEs occur in over one half of persons with normal hearing and thus
have little diagnostic significance. TEOAEs are produced by brief stimuli such as clicks. “When
a TEOAE is not seen, the suggestion is that a hearing loss is pres ent, but does not reveal whether
the prob lem is in the conductive pathway or the cochlea” (Martin & Clark, 2003, p. 159). Yellin,
Culbertson, Tanner, and Adams (2000a, 2000b) report the use of TEOAEs for early hearing screen-
ing in a well- baby nursery and note that gender differences exist among newborns.
ABR testing, sometimes called brainstem evoked response audiometry (BSER), is a test of the
auditory system in which repetitive sounds such as clicks are used as stimuli. ABR is one of several
objective electrophysiological auditory tests that mea sure the neural activity of the auditory sys-
tem. During ABR testing, the brief repetitive sounds produce electrical activity along the auditory
system, providing information about the site of a lesion.
Hearing Aids
Digital hearing aids have dramatically improved the quality of amplification for hearing-
impaired individuals. The increased quality of digital technology compared with earlier analog
hearing aids can be likened to the improved musical quality of compact discs over vinyl rec ords.
However, in spite of this new technology, no hearing aid provides the clarity, distinctness, natural-
ness, and clearness of speech and environmental sounds of the normal ear. Consequently, many
people with hearing loss are disappointed when their hearing is not returned to normal.
In general, three types of hearing aids exist: body, eyeglasses, and ear. In the body hearing
aid, the battery power and associated equipment are carried in a specially constructed body pack
or in a pocket of the person’s clothing. This hearing aid reduces the high- pitched feedback that
is troublesome to many hearing aid wearers. Because there is less miniaturization, the controls
are more easily adjusted to dif fer ent sound environments, and large headphones can be used. An
added advantage of body hearing aids is that a teacher can use a microphone and talk to several
children wearing these devices.
Eyeglass hearing aids are more comfortable for some wearers than those positioned behind or
in the ear. However, they have several disadvantages. First, because the electronics are built into
the eyeglass temple positioning arm, when the person requires new eyeglasses, the hearing aid or